{"abstract":"We propose to supersede airworthiness directive (AD) 2013-12- 01 that applies to all Rolls-Royce plc (RR) model RB211 Trent 768-60, 772-60, and 772B-60 turbofan engines. AD 2013-12-01 requires a one-time ultrasonic inspection (UI) of low-pressure (LP) compressor blades with more than 2,500 flight cycles since new or last inspection. Since we issued AD 2013-12-01, RR determined that repetitive UIs of the LP compressor blades are needed. This proposed AD would require initial and repetitive UIs of the affected LP compressor blades. We are proposing this AD to prevent LP compressor blade airfoil separations, damage to the engine, and damage to the airplane.","action":"Notice of proposed rulemaking (NPRM).","agencies":[{"raw_name":"DEPARTMENT OF TRANSPORTATION","name":"Transportation Department","id":492,"url":"https://www.federalregister.gov/agencies/transportation-department","json_url":"https://www.federalregister.gov/api/v1/agencies/492","parent_id":null,"slug":"transportation-department"},{"raw_name":"Federal Aviation Administration","name":"Federal Aviation Administration","id":159,"url":"https://www.federalregister.gov/agencies/federal-aviation-administration","json_url":"https://www.federalregister.gov/api/v1/agencies/159","parent_id":492,"slug":"federal-aviation-administration"}],"body_html_url":"https://www.federalregister.gov/documents/full_text/html/2014/05/23/2014-11919.html","cfr_references":[{"chapter":null,"citation_url":null,"part":39,"title":14}],"citation":"79 FR 29694","comment_url":null,"comments_close_on":"2014-07-22","correction_of":null,"corrections":[],"dates":"We must receive comments on this proposed AD by July 22, 2014.","disposition_notes":null,"docket_ids":["Docket No. FAA-2012-1327","Directorate Identifier 2012-NE-47-AD"],"dockets":[{"supporting_documents":[{"title":"U.S. DOT/FAA - Supporting AD Documents","document_id":"FAA-2012-1327-0014"},{"title":"U.S. DOT/FAA - Various Supporting AD Documents","document_id":"FAA-2012-1327-0008"},{"title":"U.S. DOT/FAA - Foreign Airworthiness Directive - Mandatory Continuing Airworthiness Information (MCAI)","document_id":"FAA-2012-1327-0007"},{"title":"U.S. DOT/FAA - See Attachments","document_id":"FAA-2012-1327-0005"},{"title":"U.S. DOT/FAA - See Attachments","document_id":"FAA-2012-1327-0003"}],"agency_name":"FAA","documents":[{"comment_count":0,"comment_start_date":"2014-05-23","updated_at":"2023-03-01T13:12:09.377-05:00","comment_url":"https://www.regulations.gov/commenton/FAA-2012-1327-0006","allow_late_comments":null,"id":"FAA-2012-1327-0006","comment_end_date":"2014-07-23","regulations_dot_gov_open_for_comment":false}],"supporting_documents_count":5,"id":"FAA-2012-1327","title":"Rolls-Royce plc Turbofan Engines"}],"document_number":"2014-11919","effective_on":null,"end_page":29696,"executive_order_notes":null,"executive_order_number":null,"full_text_xml_url":"https://www.federalregister.gov/documents/full_text/xml/2014/05/23/2014-11919.xml","html_url":"https://www.federalregister.gov/documents/2014/05/23/2014-11919/airworthiness-directives-rolls-royce-plc-turbofan-engines","images":{},"images_metadata":{},"json_url":"https://www.federalregister.gov/api/v1/documents/2014-11919?publication_date=2014-05-23","mods_url":"https://www.govinfo.gov/metadata/granule/FR-2014-05-23/2014-11919/mods.xml","not_received_for_publication":null,"page_length":3,"page_views":{"count":175,"last_updated":"2026-10-24 22:15:04 -0400"},"pdf_url":"https://www.govinfo.gov/content/pkg/FR-2014-05-23/pdf/2014-11919.pdf","presidential_document_number":null,"proclamation_number":null,"public_inspection_pdf_url":"https://public-inspection.federalregister.gov/2014-11919.pdf?1400762923","publication_date":"2014-05-23","raw_text_url":"https://www.federalregister.gov/documents/full_text/text/2014/05/23/2014-11919.txt","regulation_id_number_info":{"2120-AA64":{"issue":"202410","html_url":"https://www.federalregister.gov/regulations/2120-AA64/airworthiness-directives","title":"Airworthiness Directives","xml_url":"http://www.reginfo.gov/public/do/eAgendaViewRule?pubId=202410&RIN=2120-AA64&operation=OPERATION_EXPORT_XML","priority_category":"Routine and Frequent"}},"regulation_id_numbers":["2120-AA64"],"regulations_dot_gov_info":{"supporting_documents":[{"title":"U.S. DOT/FAA - Supporting AD Documents","document_id":"FAA-2012-1327-0014"},{"title":"U.S. DOT/FAA - Various Supporting AD Documents","document_id":"FAA-2012-1327-0008"},{"title":"U.S. DOT/FAA - Foreign Airworthiness Directive - Mandatory Continuing Airworthiness Information (MCAI)","document_id":"FAA-2012-1327-0007"},{"title":"U.S. DOT/FAA - See Attachments","document_id":"FAA-2012-1327-0005"},{"title":"U.S. DOT/FAA - See Attachments","document_id":"FAA-2012-1327-0003"}],"regulatory_plan":{"html_url":"https://www.federalregister.gov/regulations/2120-AA64/airworthiness-directives","title":"Airworthiness Directives"},"comments_count":0,"agency_id":"FAA","comments_url":"https://www.regulations.gov/docketBrowser?rpp=50&so=DESC&sb=postedDate&po=0&dct=PS&D=FAA-2012-1327","supporting_documents_count":5,"docket_id":"FAA-2012-1327","document_id":"FAA-2012-1327-0006","regulation_id_number":"2120-AA64","title":"Rolls-Royce plc Turbofan Engines","checked_regulationsdotgov_at":"2023-03-01T18:12:08Z"},"regulations_dot_gov_url":null,"significant":false,"signing_date":null,"start_page":29694,"subtype":null,"title":"Airworthiness Directives; Rolls-Royce plc Turbofan Engines","toc_doc":"Rolls-Royce plc Turbofan Engines","toc_subject":"Airworthiness Directives:","topics":["Air transportation","Aircraft","Aviation safety","Incorporation by reference","Safety"],"type":"Proposed Rule","volume":79}